drive: Pass through AboutResouce from server among callbacks in ChangeListLoader.

chrome/browser/chromeos/drive/change_list_processor.h

Index: chrome/browser/chromeos/drive/change_list_processor.h
diff --git a/chrome/browser/chromeos/drive/change_list_processor.h b/chrome/browser/chromeos/drive/change_list_processor.h
index d80ae383f09c05d24a52fd1a16f51cf99f7661a5..a48b382e0c7224d0c33e17ae7f1cf47f9d1d23e5 100644
--- a/chrome/browser/chromeos/drive/change_list_processor.h
+++ b/chrome/browser/chromeos/drive/change_list_processor.h
@@ -36,7 +36,8 @@ class ChangeListProcessor {
   // Class used to record UMA stats with FeedToEntryProtoMap().
   class ChangeListToEntryProtoMapUMAStats;
 
-  explicit ChangeListProcessor(DriveResourceMetadata* resource_metadata);
+  explicit ChangeListProcessor(DriveResourceMetadata* resource_metadata,
+                               const std::string drive_root_resource_id);
   ~ChangeListProcessor();
 
   // Applies the documents feeds to the file system using |resource_metadata_|.
@@ -164,6 +165,10 @@ class ChangeListProcessor {
 
   DriveResourceMetadata* resource_metadata_;  // Not owned.
 
+  // Resource ID for the user's "My Drive" root. This is provided by
+  // ChangeListLoader.
+  const std::string drive_root_resource_id_;
+
   DriveEntryProtoMap entry_proto_map_;
   std::set<base::FilePath> changed_dirs_;
   GURL root_upload_url_;